The majority of the world’s people have never seen northern lights with their own eyes. Only 2% of the world’s population lives in an area where you can see northern lights. The Finnish Lapland is one of them.

Electrically charged particles (electrons and protons) burst out from the Sun and enter the Earth’s atmosphere at a speed of up to a thousand kilometres an hour. This current of particles is called solar wind. The blasts of solar wind cause northern lights and other phenomena of space weather. A part of the particles penetrates the Earth’s magnetic field and is directed to the Earth’s polar regions, where they collide with particles of the atmosphere at an altitude of 100–300 kilometres. This creates an overwhelmingly beautiful play of nature as colours change from yellow-green to red.

In the Southern hemisphere, you can only see northern lights in the Antarctic. In the Northern hemisphere, northern lights are plentiful from the arctic circle to 75 degrees north. However, this thousand-kilometre-wide band is not accessible to all. The region is mostly sea, extending to Spitzbergen, central Greenland and northern parts of Alaska and Siberia where the population is sparse and communications poor. Canada in North America as well as Iceland, Finland and Norway in Europe are thus excellent places to observe northern lights.

The northern lights’ season begins in the Finnish Lapland in August, when nights grow longer.

Then it is possible to see ‘double northern lights’, which are northern lights in the sky and their reflection on the surface of the water. In the autumn, you can also see them as a reflection from the surface of black ice. We call this the double aurora effect”, says Ilkka Länkinen, proprietor of Arctic TreeHouse hotel, which specialises in northern lights’ tourism.

The Arctic TreeHouse Hotel is located near the arctic circle in Rovaniemi. Its rooms have been designed specifically for viewing northern lights. The northern wall of all the rooms is all glass. The rooms have been graded so that they give to different directions. All hotel guests see mostly Lappish nature from their rooms – and hopefully northern lights.

The Arctic TreeHouse Hotel is located near the arctic circle in Rovaniemi. Its rooms have been designed specifically for viewing northern lights.

The hotel monitors the northern lights’ forecasts of the Sodankylä geophysical observatory, and it also uses the local Aurora Alert application which notifies the hotel guests’ mobile phones at any time when northern lights are visible.

“I can say from experience that if you stay three nights in the hotel, you will see northern lights with a 90% probability.”

The northern wall of all the rooms is all glass. You can observe the northern lights in peace and quietness from the room. In the picture the reflection of the exit-sign can be seen in the middle of the northern lights.

On a clear night, the average probability of seeing northern lights in the Finnish Lapland at 9 p.m. exceeds 50%. The probability peaks about an hour before midnight, which is the magnetic midnight, and the disturbances of the Earth’s magnetic field are at their greatest. The possibility of seeing northern lights increases the further north you go.

According to the Finnish Meteorological Institute, northern lights are mostly seen in Finland in northern Lapland, at around the latitude of Kilpisjärvi. When the sky is clear, northern lights are observed there on an average of three nights out of four. In order to see northern lights every night you have to go to the Arctic Sea coast in northern Norway.

“We always emphasise to the hotel guests that northern lights are a natural phenomenon, whose occurrence does not depend on us. Till now the tourists have been understanding that they cannot always be seen”, says the hotel manager, Katri Kerola.

“The guests come to the hotel in the winter mainly because of northern lights. Northern lights cause a nice kind of grouping among the guests. In a little street, twenty people meet in the middle of the night, thrilled and joyful, to view nature’s theatre. The Instagram account of our hotel is filled with visitors’ pictures of northern lights. I come from here, and I too stop to watch them, even if I was in a hurry to get somewhere. Northern lights are Lappish mindfulness.”

A silent nature experience

The gustiness of the solar wind causing northern lights is known to vary in eleven-year cycles. It is connected to the number of sun spots on the surface of the Sun. The probability of the occurrence of northern lights can be predicted by observing the Sun’s surface.If a blast is observed on the surface of the Sun, it can be deduced that northern lights will occur in one or two days.

Staying at the Arctic TreeHouse Hotel is a calming experience. Even if northern lights are not to be seen, you can lie on your large bed and stare at the beautiful forest landscape in silence. Watching television does not even occur to you.

“We have intentionally kept the hotel quiet. There are double-insulated double glasses and a grass thatch overhead, insulating sounds well. The television set is intentionally hidden in the rooms”, Länkinen sneers and emphasises that the hotel was specifically designed to give a nature experience.

“You can watch nature peacefully indoors, irrespective of the weather. The architect’s starting points were a good view, peacefulness and a safe nature experience. Nature comes very near, because the large window makes the guest feel a part of nature”, Ilkka Länkinen says.

Particularly Asians have found the hotel.

“In addition to the British, plenty of tourists from Japan and Singapore come here. China is growing at 300% annually. Many weddings and engagement parties have been held under the glow of northern lights.”

At the Arctic TreeHouse hotel, you can watch northern lights both in water and in the air. At the Metsäkyly forest spa, you can watch northern lights in a jacuzzi after the sauna.

Extreme experience. You can watch northern lights at the jacuzzi of the Metsäkylä Spa.

You can also climb up in the air.

“We offer the hotel guests the possibility to view northern lights at the height of two kilometres. A seven-seat light aircraft takes you on an hour’s trip to where northern lights appear. Because up in the air visibility is 50 kilometres, we will surely have a show of northern lights somewhere.”

Aurora Alert

The Sámis believed that northern lights are created when a fox waves its tail in the snow, creating sparks, “fox fires”, as they are called in Finnish. Picture from the norther lights-documentary from Arktikum.

Aurora Alert is a local northern lights’ forecasting system operating in Rovaniemi. It forecasts and observes northern lights and notifies the customer of the location of northern lights in the sky. Essential in the service is that it only indicates the northern lights the customer can observe.

“The forecast of the Sodankylä geophysical observatory indicates the probability of the occurrence of northern lights. Aurora Alert also takes cloud masses into account. It indicates when northern lights are visible with your own eyes”, explains data communications engineer Reijo Kortesalmi, the developer of the application.

Aurora Alert sends a forecast, probability percentage and alarm to the mobile phone. The application is based on signal processing and colour analysis. Aurora Alert uses its local sensors located in Rovaniemi, serving the northern lights’ tourists of the Rovaniemi area.

Aurora Alert combines data from many sources.

“An indicative forecast comes every night at eight o’clock. The probability percentage indicates what you can observe with your own eyes. A real-time alert comes, for example, if the local cloud curtain opens for five minutes.”

The application also indicates the intensity of the northern lights.

“Number one means that northern lights are clearly observable with one’s own eyes. Number five means that northern lights light up the whole sky. The intensity of northern lights may vary in the course of the evening. At 11 p.m., northern lights may be of level 1, but at 2 a.m. the intensity may be five”, says Kortesalmi.

The duration of northern lights varies as well.

“Weak northern lights may appear for a few minutes, but strong northern lights appear from half an hour to one and a half hours.”

Kortesalmi takes his holiday from April to July, when northern lights are not seen in Rovaniemi. Forecasting and alerting starts again in August.

“Aurora Alert definitely gives the most precise information on northern lights in Rovaniemi.”

Ari Turunen (2017)

The Northern Lights Zone in the Northern Hemisphere

The best chances of seeing northern lights are on a thousand-kilometre-wide zone north of the arctic circle.

Arctic TreeHouse Hotel

Although northern lights are an important part of the activities of Arctic TreeHouse Hotel, Ilkka Länkinen recommends a trip to Lapland in the summer. 95% of the world’s people cannot see the midnight sun, Länkinen notes.Inhabitants of Rovaniemi often play golf at midnight.

The northern lights’ season begins in August and ends in April.The Sodankylä geophysical observatory provides a 72-hour northern lights’ forecast and a long-term seven-day forecast. Aurora Alert takes the notice of clouds as well. It notifies the customer’s mobile phone when the northern lights can be seen.